Al, Si, Fe AND SILICA PRECIPITATION IN ELECTRIC ORGAN FROM A LIVING ELECTRIC FISH.

BARRERA, F., CESARETTI, N. N., AND PRADO FIGUEROA, M.

Pucon

Congreso; III-Neurotoxicity Society Meeting: Neurochemical Mechanism for Neurodegenerative Disorders.; 2007

Neurotoxicity Society

Aluminum, iron and silicon were observed in electrocytes (Rajidae family) by SEM-EDS. Also, electric organ segments, cryostat sections and subcellurar fractions were observed using mineralogical techniques. X-ray diffraction analysis showed low-quartz variety. When we observed thought cresset polarized illumination, which allows for mineral identification, chalcedony was distributed in the electrocyte cytoplasm, nerves and all the fractions. It is rounded in shape, first order of birefringence color and a with undulatory extinction angle. Chalcedony (SiO2) is acrystalline variety of silica and also is present in fossilization processes in different organic matter, its precipitation occurring at specific pH (7-8) and oxidation potential (Eh)(0.1 to 0.2) conditions. This observation support the idea of was report in geological environments. May be, electric organ silicification is also in relation with the enzyme silicatein. This is the first mention that chalcedony was in relation with cholinergic nerve terminals, from a living animal.